Key resources table.

Reagent type (species) or resource	Designation	Source or reference	Identifiers	Additional information
Gene (E. coli)	ExoⅢ	GenBank	GeneID:946254
Strain, strain background	Rosetta(DE3) Competent Cells	LGC Biosearch Technologies	70954
Peptide, recombinant protein	ExoⅢ	NEB	NEB#M0206V
Peptide, recombinant protein	T7 exonuclease	NEB	NEB#M0263L
Peptide, recombinant protein	LbCas12a	NEB	NEB#M0653S
Peptide, recombinant protein	T4 gp32	Beyotime Biotech. Inc, China	D7057S
Peptide, recombinant protein	SSB (E. coli)	Beyotime Biotech. Inc, China	P7415
Recombinant DNA reagent	pET-30a (plasmid)	Addgene	EMD Biosciences	Protein expression
Commercial assay or kit	HisSep Ni-NTA 6FF Chromatography	Yeasen Biotechnology Co., Ltd, China	20503ES10	Protein purification
Commercial assay or kit	ClonExpress II One Step Cloning Kit	Vazyme Biotech, China	C112
Commercial assay or kit	T7 in vitro transcription kit	Vazyme Biotech, China	TR101 V22.2	crRNA synthesis
Commercial assay or kit	TURBO DNase	Thermo Fisher Scientific, Massachusetts, USA	AM2238	crRNA synthesis
Commercial assay or kit	RPA	TwistAmp Basic	TABAS03KIT
Commercial assay or kit	MIRA (Basic type)	Amplification Future company	WLB8201KIT
Commercial assay or kit	RPA	TwistAmp exo	TAEXO02KIT
Commercial assay or kit	MIRA (Fluorescence type)	Amplification Future company	WLE8202KIT
Sequence-based reagent	FQ reporter	This paper	Sunya Biotechnology Co., China	5’-FAM-TTATT-BHQ1-3’
Sequence-based reagent	Probe 1	This paper	Sunya Biotechnology Co., China	CAAACCCAGAGCCAATCTTATCT
Sequence-based reagent	Probe 2	This paper	Sunya Biotechnology Co., China	CGGGTGGGCGGAAAACTATTTC
Sequence-based reagent	Probe 3	This paper	Sunya Biotechnology Co., China	AGTCCGTTTGTTCTTGTGGC
Sequence-based reagent	crRNA	This paper		GGUAAUUUCUACUAAGUGUA GAUAACAGCACAUGCAGAAUCAU
Software	PyMOL	DeLano Scientific
Software	Mx3500P	Agilent		Fluorescence monitoring
Software	Graphpad	Dotmatics	Version 9.0.0